Scaning FC_LUN's in RedHat linux

# fdisk -l 2> /dev/null | egrep '^Disk' | egrep -v 'dm-' |wc -l

# ls /sys/class/fc_host/
host1  host8

For FC
#  echo "1" > /sys/class/fc_host/host1/issue_lip
#  echo "1" > /sys/class/fc_host/host8/issue_lip

For SCSI

#  echo "1" > /sys/class/scsi_host/host1/scan
#  echo "1" > /sys/class/scsi_host/host8/scan


# fdisk -l 2> /dev/null | egrep '^Disk' | egrep -v 'dm-' |wc -l